Answer:
25x^2 - 16y^2 - 400 = 0
Step-by-step explanation:
Step-by-step explanation:
a) 6-9b=3a
First:Subtract
3b=3a
Second: Devide
3b/3a
=(3÷3)(b÷a)
=1b/a
= b/a
B) 6b+2a=3a
First:Transpose (Group the like terms. signs will change.)
-3a+2a=-6b
=-1a=-6b
Second:Divide
=-1a/-6b:(-1÷-6)(a÷b)
=1a/6b
=a/6b
C)a/3=b+2
First: Transpose
a=3+2+b
=a/6+b
Answer:
$10 coins: 21
$20 coins: 24
Step-by-step explanation:
heyy me again
So we can create 2 equations where
x = number of $10 coins
y = number of $20 coins:
x + y = 45
10x + 20y = 690
we can move equation 1 around so that we can get a value of x
x = 45 - y
now we can substitute x into the second equation
10(45 - y) + 20y = 690
450 - 10y + 20y = 690
10y = 240
y = 24
Now plug in y back into the first equation
x = 45 - y
x = 45 - 24
x = 21
228/28 1/2 ÷ 4 3/4 = 57/2 × 4/19= 228/38 = 6
Btw i did keep change flip
Every point on the line 3/7x -1 is a solution
Unless there is another line provided...
